AngularJS injectors understand aliased for core injectables such as
$rootScope in unit tests. If you surround your injected object with underscores
_$rootScope_ it will be understood and injected into your test by Angular. This allows you to use a local alias of the same name.
The "R" word. Refactoring. The first step in refactoring code is to make sure we are covering the existing code with tests. If we aren't refactoring against tested code, we are just changing stuff. In this lesson, we'll start taking a look at some code that needs refactoring, and get test coverage reports setup.